As portable electronic devices become more compact, and the number of functions performed by a given device increase, it has become a significant challenge to design a user interface that allows users to easily interact with a multifunction device. This challenge is particular significant for handheld portable devices, which have much smaller screens than desktop or laptop computers. This situation is unfortunate because the user interface is the gateway through which users receive not only content but also responses to user actions or behaviors, including user attempts to access a device's features, tools, and functions. Some portable communication devices (e.g., mobile telephones, sometimes called mobile phones, cell phones, cellular telephones, and the like) have resorted to adding more pushbuttons, increasing the density of push buttons, overloading the functions of pushbuttons, or using complex menu systems to allow a user to access, store and manipulate data. These conventional user interfaces often result in complicated key sequences and menu hierarchies that must be memorized by the user.
Many conventional user interfaces, such as those that include physical pushbuttons, are also inflexible. This is unfortunate because it may prevent a user interface from being configured and/or adapted by either an application running on the portable device or by users. When coupled with the time consuming requirement to memorize multiple key sequences and menu hierarchies, and the difficulty in activating a desired pushbutton, such inflexibility is frustrating to most users.
A touch-sensitive screen is often used by a portable device because the screen can render different types of virtual service control objects such as virtual push buttons associated with different services. A user can activate these virtual service control objects through different types of finger contacts with the touch screen such as finger tap gestures and finger swipe gestures. For example, a finger tap gesture on an alphanumeric key icon enters the user-selected character into a specific field on the touch screen and a finger swipe gesture may move a slider icon from one position to another position by a specific distance.
Unfortunately, conventional approaches fail to recognize and/or use differences between finger tap gestures and finger swipe gestures on the touch screen display that can be used to make the device respond more efficiently to such gestures (e.g., responding faster to tap gestures and moving a slider icon by a distance that more accurately reflects the touch gesture). Accordingly, there is a need for portable devices with touch screen displays that respond more accurately and efficiently to touch input by a user.